<template>
  <div id="home">
    <nav-bar class="home-nav">
      <div slot="center">购物街</div>
    </nav-bar>

    <tab-control class="tab-contorl" :titles='["流行", "新款", "精选"]' @tabClick="tabClick" ref="tabControl1" v-show="isTabFixed" />

    <scroll class="content" ref="scroll" :probe-type="3" @scroll="contentScroll" :pull-up-load="true" @pullingUp="loadMore">
      <home-swiper :banners="banners" @swiperImageLoad="swiperImageLoad" />
      <recommend-view :recommends="recommends" />
      <feature-view />
      <tab-control class="tab-contorl" 
        :titles='["流行", "新款", "精选"]' 
        @tabClick="tabClick" ref="tabControl2" />
      <goods-list :goods="showGoods"></goods-list>
    </scroll>
    
    <back-top @click.native="backClick" v-show="isShowBackTop"></back-top>
    
  </div>
</template>

<script>
  import HomeSwiper from "./childComps/HomeSwiper"
  import RecommendView from "./childComps/RecommendView"
  import FeatureView from "./childComps/FeatureView.vue"

  import NavBar from "components/common/navbar/NavBar"
  import TabControl from "components/content/tabControl/TabControl"
  import GoodsList from "components/content/goods/GoodsList"
  import Scroll from "components/common/scroll/Scroll"
  import BackTop from "components/content/backTop/BackTop"
  
  import {getHomeData, getHomeGoods} from "network/home"
  import {debunce} from "common/utils"

  export default {
    name: "Home",
    components: {
      HomeSwiper,
      RecommendView,
      FeatureView,
      NavBar,
      TabControl,
      GoodsList,
      Scroll,
      BackTop
    },
    data() {
      return {
        // result: null
        banners: [],
        recommends: [],
        goods: {
          "pop": {page: 0, list: []},
          "new": {page: 0, list: []},
          "sell": {page: 0, list: []}
        },
        currentType: "pop",
        isShowBackTop: false,
        tabOffsetTop: 0,
        isTabFixed: false
      }
    },
    computed: {
      showGoods() {
        return this.goods[this.currentType].list
      }
    },
    created() {
      //1.请求多个数据
      this.getHomeData();

      //2.请求商品数据
      this.getHomeGoods("pop");
      this.getHomeGoods("new");
      this.getHomeGoods("sell");
    },
    mounted() {
      //1.图片完成事件监听
      const refresh = debunce(this.$refs.scroll.refresh, 200);
      this.$bus.$on("itemImageLoad", () => {
        refresh();
      })
    },
    methods: {
      getHomeData() {
        getHomeData().then(res => {
          this.banners = res.data.data.banner.list;
          this.recommends = res.data.data.recommend.list;
        });
      },
      getHomeGoods(type) {
        const page = this.goods[type].page + 1;
        getHomeGoods(type, page).then(res => {
          this.goods[type].list.push(...res.data.data.list);
          this.goods[type].page += 1;
          this.$refs.scroll.finishPullUp()
        });
      },
      tabClick(index) {
        switch(index) {
          case 0:
            this.currentType = "pop";
            break;
          case 1:
            this.currentType = "new";
            break;
          case 2:
            this.currentType = "sell";
            break;
        }
        this.$refs.tabControl1.currentIndex = index;
        this.$refs.tabControl2.currentIndex = index;
      },
      backClick() {
        this.$refs.scroll.scrollTo(0, 0);
      },
      contentScroll(opsition) {
        this.isShowBackTop = (-opsition.y) > 1000
        this.isTabFixed = (-opsition.y) > this.tabOffsetTop
      },
      loadMore() {
        this.getHomeGoods(this.currentType)
      },
      swiperImageLoad() {
        this.tabOffsetTop = this.$refs.tabControl2.$el.offsetTop
        console.log(this.$refs.tabControl2.$el.offsetTop); 
      }
    }
  }

</script>

<style scoped>
  #home{
    height: 100vh;
  }
  .home-nav{
    background-color: var(--color-tint);
    color: #FFF;
    /* position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    z-index: 9; */
  }
  .tab-contorl{
    position: sticky;
    z-index: 9;
    top: 44px;
  }
  .content{
    /* height: 300px; */
    overflow: hidden;
    position: absolute;
    top: 44px;
    bottom: 49px;
    left: 0;
    right: 0;
  }
</style>